Percival Prentice 1 prepic016


                           PART I-DESCRIPTIVE


     12.  Trimming tabs

          There are two sets, (30) and (33), of elevator and rudder
          trimming tab handwheels, one set to the left of each seat.
          They embody trim indicators and operate in the natural
          plane and sense.

          A servo tab is fitted to each aileron and may be adjusted
          on the ground for trimming purposes.

     13.  Flaps control

     (i)  The flaps are pneumatically operated and controlled by
          the selector lever (29) on the central throttle box.   This
          lever has three positions, UP, TAKE-OFF (maximum
          lift position), and DOWN, the TAKE-OFF position being
          gated.

    (ii)  The flaps position indicator (19) is on the right-hand side
          of the instrument panel.

     14.  Wheel brakes

          A brakes lever (40) is fitted on each control column spade
          grip, and the brakes may be operated by either lever,
          being locked on for parking by means of the small clamps
          (32) on the forward side of each control column below the
          spade grip.   Pressure at each brake is shown by the lower
          needles on the pneumatic supply pressure gauge (20).   The
          pressure with brakes fully applied, and rudder central,
          should be 100 lb./sq. in. at each wheel.

    ENGINE CONTROLS
    
     15.  Throttle and mixture controls

          Two throttle levers are fitted, one (28) on the central
          pedestal and a second (35) on the left-hand side of the
          cockpit.   Mixture control is automatic, a weak mixture
          being obtained at throttle settings giving -2 lb./sq. in.
          boost or less.   A friction adjuster knob (5) on the left-hand
          side of the central throttle box adjusts the friction for
          both throttle levers.
    
     16.  R.p.m. control levers

          Two levers (26) and (36) are fitted, one alongside each
          throttle lever.   They are set forward to INCREASE and
          back to DECREASE r.p.m. and the governed range is
          1,900 and 2,500 r.p.m.